Our projected research for the forthcoming year (September 1, 1978 to August 31, 1979) will be directed toward three main areas: Antibodies: We are exploring the mechanism of activation of complement, using complexes of bivalent IgG antibody and bivalent Dnp hapten as the activating material. Crosslinking reagents will be employed to stabilize these complexes and also Clq-antibody complexes. Nucleohistone: We are attempting to visualize the conformational change which occurs at low ionic strength by electron microscopy. We are using covalent probes to explore at low ionic strength by electron microscopy. We are using covalent probes to explore the groups involved in the transition. Finally we are looking at the kinetics and thermodynamics of transfer of nucleosomes from from one piece of DNA to another. Lipoproteins: We are developing methods for the isolation and characterization of remnant particles in serum, particularly utilizing our newly developed technique of laser scattering from centrifuged solutions. We are also attempting to locate the B protein on chylomicrons using ferritin-labelled antibodies.